Operation Manual

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SNMP
Simple Network Management Protocol (SNMP) is an
ApplicationLayerprotocoldesignedspecicallyfor
managing and monitoring network devices. Simple
Network Management Protocol (SNMP) is a popular
protocol for network management. It is used for
collectinginformationfromandconguringnetwork
devices such as; servers, printers, hubs, Switches, and
routers on an Internet Protocol (IP) network. SNMP is
used to exchange management information between
a network management system (NMS) and a network
device. A manager station can manage and monitor the
Switch through their network via SNMPv1, v2c and v3.
An SNMP managed network consists of two components;
agents and a manager.
An agent translates the local management information
from the managed Switch into a form that is
compatible with SNMP. SNMP allows a manager
and agents to communicate with each other for
the purpose of accessing Management Information
Bases (MIBs). SNMP uses an extensible design, where
theavailableinformationisdenedbyMIBs.MIBs
describe the structure of the management data of a
device subsystem; they use a hierarchical namespace
containingObjectIdentiers(OID).EachOIDidentiesa
variable that can be read or set via SNMP.
The manager is the console through which network ad-
ministrators perform network management functions.
Several versions of SNMP are supported. They are v1,
v2c,andv3.SNMPv1,whichisdenedinRFC1157“A
Simple Network Management Protocol (SNMP)”, is a stan-
dardthatdeneshowcommunicationoccursbetween
SNMP-capabledevicesandspeciestheSNMPmessage
types. Version 1 is the simplest and most basic of ver-
sions. There may be times where it’s required to support
olderhardware.SNMPv2c,whichisdenedinRFC1901
“IntroductiontoCommunity-BasedSNMPv2,”RFC1905,
“Protocol Operations for Version 2 of the Simple Network
ManagementProtocol(SNMPv2)”,andRFC1906“Trans-
port Mappings for Version 2 of the Simple Network Man-
agement Protocol (SNMPv2)”. SNMPv2c updates protocol
operations by introducing a GetBulk request and authen-
tication based on community names. Version 2c adds
several enhancements to the protocol, such as support
for “Informs”. Because of this, v2c has become the most
widely used version. Unfortunately, a major weakness
of v1 and v2c is security. To combat this, SNMP v3 adds
a security features that overcome the weaknesses in
v1 and v2c. . If possible, it is recommended that you use
v3- especially if you plan to transmit sensitive informa-
tion across unsecured links. However, the extra security
featuremakescongurationalittlemorecomplex.